The history of printing by presses and other methods and devices is a long and honored chain of steady invention and improvement. As the demands of information dissemination continue to grow, and as competition for attention in advertising, graphic decoration and education among various media continues to grow, the techniques and technologies of printing move forward to continue the historical progression. The within described invention seeks to extend this line of invention into new areas of graphic attraction heretofore unattained, and usefully introduces printed effects considered too difficult or costly for mass production.
Complex and colorful imprinted graphics, specifically tactile graphics on packaging and display cards with the effects of layering, embossing, engraving and etching are increasingly in demand to distinguish products and displays from less fully-featured printed products. The difficulties in achieving such dramatically new printed effects are considerable, especially when compared to the simplicity and economy of standard flat printing processes. The present invention addresses in particular the forms of packaging in flexible materials such as bags and wrappers, as well as flat forms of printing such as cards and boxes, and the problems inherent in highly decorative tactile deposits of print materials to form complex designs. To illustrate the evolving nature of print methods and devices, declarant himself is a part of the progression, having addressed the problems of depositing of complex etched or embossed effect designs by printing on substrates in the sign industry, which developments have issued in U.S. Pat. Nos. 5,082,703 and 4,933,218, both entitled Sign With Transparent Substrate, issued to Longobardi. In those disclosures, declarant describes and claims signs and methods of producing signs which embody extreme printing achievements. Specifically, the described techniques involve the deposit of extraordinarily thick ridges of viscous ink (or paint material, the use of the word "ink" in this disclosure is intended to include various liquid or semi-liquid materials suitable for producing printed designs of the described types) on generally rigid flat plate substrates. The resultant product is suitable for display signage. Further, these disclosures also present associated techniques of achieving embossed and etched effects, including curing, enhancement and fixation instructions. In the present invention, applicant has extended the long history of printing developments by taking the techniques and processes of the '703 and '218 patents cited above into new territory and materials heretofore thought impossible, ineffective or too costly.
The problems presented by moving from imprinting on a flat, substantially rigid substrate in single or limited production runs to imprinting on a flexible medium in large volume production runs have required overcoming numerous obstacles by development and experimentation. Conventional sheet or continuous roll presses and methods are unable to accommodate the demands of the complex deposits required of the raised and textured effects which are the objects of this invention, and design of wholly new and complex printing equipment and processes is required and achieved in this invention.
While printing technology generally forms the background of the present invention, the '703 and '218 patents to Longobardi cited above disclose the state of the art up to development of the present invention for deposit of printed designs including etched or embossed appearances on a substrate. The designs achieved in that environment which related essentially to transparent substantially flat and rigid substrates such as glass or plastic suitable for signage would be usefully applied to new media in packaging, advertising and art printing if they could be adapted to other substrate material such as sheet mylar and other plastics, paper, cardboard and other flexible sheet and continuous roll types of materials. The designs achieved in the '703 and '218 patents were enabled by the novel combination of layers of ink applied on the surfaces of the substrates, where the designs included a thick ridge of ink at the edges of the designs, which ridge could be further textured to provide complex tactile and visually striking surfaces, and the final deposit over the formed and shaped designs of various topping strata such as adhered thin sheets or spray or powder deposits.
While printing of new attractive designs on sheet material has enjoyed many advances in recent years, as evidenced in such media as magazine covers and advertising inserts, mylar food bag type packaging, and collectible printed media such as trading cards, the new effects described in '703 and '217 patents have not been achieved in imprinting on mass produced flexible substrate media until development of the within described invention. Illustrating one extreme difference in translating from the traditional printing processes to the demands of the new heavily tactile embossed effect designs, ordinary deposit of print material such as colored inks are in the small micron ranges of thicknesses, where the range of thicknesses in at least parts of the new tactile designs must be in the extraordinary range of significant fractions of inches, typically about 0.01 inches or greater in order to provide ridges and patterned surfaces that provide significant visual design information to the observer. Clearly, traditional presses and printing methods are not adaptable to the new requirements of material deposit on flexible substrate material by lack of adjustability and accommodation of the additional deposit, curing and overlay steps necessitated.
Further, while printing methods other than presses, such as jet-printing or drum-and-toner deposit methods can produce significant deposit thicknesses of ink or paint material, significant texturing effects such as embossed or etched effects are unachievable because a press or imprint step is generally missing and an additional cover surface or sealer is also typically required and unavailable in jet-print processes.
In light of the above, it is an object of the within invention to enable richly textured printed designs on flexible sheet material. It is also an objective of the invention to define a process that can produce the textured printed designs in a high volume, high speed production environment. A further objective is to adapt the designs achieved on rigid substrate materials to the more demanding flexible sheet material substrates. Yet another objective of the invention is to define a process that can achieve complex printed designs on either the inside of a packaging enclosure for viewing from the outside or imprinting on the outside alternatively if desired.